Such a gas sensor proceeds, for example, from the German patent DE 102 57 284 A1. In the case of this gas sensor, wherein the sensor heating device is operated in a clocked circuit in order to introduce the heat output required at any one time into the sensor element, the sensor heater is provided with two supply lines. Moreover, provision is made for a pump current line, a measuring line as well as a reference pump current line for the pump cell and the Nernst cell. A common ground line is used for the pump cell and the Nernst cell.
Connectors, which must contain six terminals, are required for establishing contact for such a broadband probe. Additional lines and connecting pins require an additional manufacturing complexity and cause additional costs. Moreover, a use of standard connectors is not implicitly possible. It is also a disadvantage that a drop in voltage between the ground of the internal combustion engine and the ground of the circuit arrangement, which, for example, is constituted by a control unit, is variable depending on current load; and if the connection is corroded, said drop in voltage can exceed approximately 1V and thereby the Nernst voltage.
Moreover, a disturbance in the output signal, which is not desirable, can arise in the sensor element by way of the coupling of the clocked heating device with the Nernst cell. A coupling of the heating current into the signal line can cause considerable disturbances in the operation of the gas sensor.